Fig. 4: Ultrafast magnetoacoustics in AFM thin films. | npj Computational Materials

Fig. 4: Ultrafast magnetoacoustics in AFM thin films.

From: Excitation and detection of coherent sub-terahertz magnons in ferromagnetic and antiferromagnetic heterostructures

Fig. 4

a Schematic of Al/MgO/Fe50Mn50/Pt heterostructure as an example for acoustic excitation of sub-THz magnons in an AFM thin film and their detection via electromagnetic (EM) wave emission. In both magnetic sublattices of the Fe50Mn50 layer, the magnons (denoted by Δm(s)) of different modes n are excited by fs-laser-induced ultrashort acoustic pulse εzz which has a peak amplitude εmax and a duration τ. The excited magnons pump spin current Js into the Pt layer, which is converted to transverse charge current Jc via iSHE. Jc emits EM wave via electric dipole radiation. b Analytically calculated frequencies of the n = 1 and n = 2 mode magnons and the antiferromagnetic (AFMR) mode (n = 0) magnon as a function of FeMn film thickness (d). The frequencies for the case of d = 15 nm are labeled.

Back to article page